Glossary

GLOSSARY

Following is a list of jewellery vocabulary that will help you to understand and appreciate jewellery:

9K Gold:  9 karat gold (9K) is 9 parts gold to 15 parts other metal. Sometimes 9K gold is hallmarked as 375, being 37.5% pure gold.

14K Gold:  14 karat gold (14K) is 14 parts gold to 10 parts other metal. 14K Gold is not widely used in Australia, it is mostly used in America.

18K Gold:  18 karat gold (18K) is 18 parts gold to 6 parts of other metal. Sometimes 18K gold is hallmarked as 750, being 75% pure gold.

Asscher cut:
A square step cut diamond named after its inventor, Joseph Asscher.

Angel Fire cut: The same shape as an Asscher cut, but trademarked for Moissanite jewels only, with different faceting.

Baguette:  A style of step cutting for small, rectangular or trapeze-shaped gemstones. Baguettes are used as accent or side stones.

Bail:  A metal finding that is folded closed, from which a pendant, may be hung from a chain or cord.

Band:  A ring that is the same width all around the circumference.

Bar Setting:  A diamond setting style that holds each diamond in by a thin bar, shared between the two diamonds.

Beauty:
  The beauty of a jewel is determined by its colour, brilliance, "fire", and scintillation (lustre).

Bezel:  A bezel setting is when a rim of metal that holds the jewel and completely surrounds it.

Blemishes: The term blemish is used when the diamond has scratches or marks on the external area of the stone.

Brilliance:  The brilliance of a jewel is created by cutting designs that use the jewel's refractive index and is measured by the amount of light that enters the jewel and is reflected back to the viewer.

Brilliant Cut: Brilliant cuts are scientifically found to reflect the most light from within the stone, and often are considered to have the most brilliance of all cuts.  A round brilliant cut diamond has 58 facets.

Briolette:  A gemstone with a tear-drop shape, a circular cross-section and brilliant-style facets or occasionally rectangular, step-cut style facets.

Cabochon:  A facet-less style of cutting that produces a smooth surface. They can be in many shapes, including round with high domes to square.

Carat:  A unit of weight for jewels. One carat is equivalent to 100 points or one-fifth of a gram. A 0.85 Carat stone is the same as an 85 pointer.

Centre Stone:  The main stone in a piece of jewellery with multiple stones. This stone is usually the largest and most prominent.

Certificate or "Cert":  Another term for a diamond grading report.  A document produced by a 3rd party that describes a diamond's characteristics.

Channel Setting:  Used most frequently for wedding and anniversary bands and may used to accent centre stones. The diamonds are set in a channel with no metal separating the stones.

Clarity:  Diamonds have internal features, called inclusions, and surface irregularities, called blemishes.  Together, they're called clarity characteristics. A diamond clarity grade is determined by the relative absence of clarity characteristics.

Cleavage:
  The natural way a mineral breaks, along certain planes based on its internal crystalline structure.

Cluster Setting:  This setting surrounds larger centre stone with several smaller stones. It is designed to create a beautiful larger setting from many smaller stones.

Colour:  Diamonds are graded on a colour scale established by the GIA and ranked from ‘D' down to ‘Z'. A ‘D' colour is the top colour grade (colourless) and a  ‘Z' has noticeable tints of colour. A greater colour saturation than a ‘Z', is considered a Fancy Coloured Diamond.

Conflict (blood) Diamond: In relation to diamond trading, conflict diamond (also called a blood diamond) refers to a diamond mined in a war zone and sold to finance an insurgency, in Africa.

Corundum: Corundum is a very hard mineral. It is called ruby or sapphire, depending on the colour. In its rare pure form, corundum is colourless and called white sapphire.

Crown: The part of any faceted diamond above the girdle. It consists of a large flat area on top called a table and several facets below it.
Crown angle: The angle between the girdle plane and the bezel facets.

Crown Height Percentage:
  The distance between the girdle and the table plane expressed as percentage of the average girdle diameter.

Culet:
  This is the small facet polished across what would otherwise be the sharp point or tip of the pavilion of a faceted stone, especially a round brilliant cut.

Cushion Cut:  A shape like a square pillow with curved sides and rounded corners.

Cut:
  Cut refers to the angles and proportions a skilled craftsman creates in transforming a rough diamond into a polished diamond. Based on scientific formulas, a well-cut diamond will internally reflect light from one mirror like facet to another and, disperse and reflect it through the top of the stone. Diamonds that are cut too deep or too shallow lose or leak light through the side or bottom, resulting in less brilliance, and ultimately value.

Cut Quality:  also called Make, refers to the proportions and finish of a gemstone.

Depth Percentage:
  On a diamond grading report, you will see two different measurements of the diamond's depth- the actual depth in millimetres and the depth percentage which expresses how deep the diamond is in comparison to how wide it is.

Diamond:
A diamond is the hardest known natural substance. It is crystallized carbon. Diamonds are mined in their rough form and then, cut and polished to reveal their brilliance.

Diamond Grading Reports:   There are many recognized gemmological laboratories that can grade your diamond for a fee. The most well know is the GIA, Gemmological Institute of America.

Dispersion
: The spreading of white light into its spectral colours. This typically occurs in the crown area of a diamond. Dispersion is also referred to as fire.

Drop Earring:  Any earring that hangs below the earlobe, also called a dangle earring.

Durability:  The durability of a jewel is determined by its hardness, or resistance to scratching, and its toughness, or resistance to chipping or cleaving.

Earring backing: A disk or bead that fits over an earring post and holds the earring securely in place. Sometime it is referred to as a butterfly backing.

Emerald Cut: A style of cutting a diamond in which the outline is a rectangular shape with cut corners and the shape of the facets are rectangular and trapezoid. An emerald is a step-cut

Eye-clean:
Refers to a gemstone that has no inclusions or blemishes visile to the naked eye.

Facet:  These are the tiny surfaces polished onto a rough diamond that gives a finished diamond its shape. The way light interacts with these facets affects a diamond's brilliance and sparkle. A round brilliant cut gemstone has a total of 57 or 58 facets including the culet.

Fancy Cut: A diamond shape other than Round; such as Baguette, Emerald, Pear, Marquise, Princess, Oval, Heart, Radiant, and Asscher cuts.

Feather: A type of inclusion or flaw within a diamond that looks like a feather. It is described often as a small crack or fissure.

FI:  GIA Clarity Grade for Flawless, no blemishes or inclusions.

Filigree:
  Gold or silver wire that have been twisted into patterns and soldered into place.

Fire:
  The dispersion of a jewel combined with the cutting design results in the "fire," or the breaking of light rays into the spectrum of colours and is measured by the amount of colour flashes viewed when the jewel is moved in various lighting conditions.

Fracture Filling: A process that injects a substance into a diamond to hide inclusions.

Fluorescence:  When exposed to ultraviolet light, a diamond may exhibit a more whitish, yellowish, or bluish tint, which may imply that the diamond has a property called fluorescence. Diamond grading reports often state whether a diamond has fluorescent properties.  Fluorescence is not considered a grading factor, only a characteristic of that particular diamond. The most common colour is blue, and the term “blue white” is used to describe the diamonds intense fluorescence that is visible in normal daylight.  When considering purchasing a diamond, a rating of “Faint” or “Medium” fluorescence should not be a concern.
GIA, Gemmological Institute of America:  A non-profit teaching institute considered the standard bearer in the grading of diamond and coloured gemstones.

Girdle:  The outer edge of a cut jewel that separates the crown from the pavilion. Sometimes the girdle is polished and sometimes it is not polished. Ideally the width of the girdle should be even and proportional to the cut of the stone.

Growth Lines:
These can be considered internal flaws, and can often be seen only by rotating the diamond very slowly. They appear as small lines within diamond or Moissanite.

Hardness:  Hardness is the resistance to being scratched. Hardness is measured using the Mohs scale. The hardest gemstone is diamond, which is 10 on the Mohs scale; the second hardest gemstone is Moissanite, which is 9.25 on the Mohs scale.

Hoop Earring:  A circular-shaped earring.
Inclusion:  Internal characteristics in a gemstone.  Inclusion can be bubbles, crystals, carbon spots, feathers, clouds, pinpoints, or other impurities, or even cracks and abrasions.

I1, I2, & I3:  GIA Clarity grades for Imperfect, obvious inclusions that usually are eye-visible.

IF or Internally Flawless: "IF" in GIA's Clarity Grading System, means there are no inclusions when examined by a skilled grader, and only insignificant blemishes under 10X magnification.

Invisible Setting: Diamonds that are set next to each other with the metal of the setting concealed underneath the diamonds to create the illusion of a larger diamond.

Karat:
The measure of the purity of gold. 24K is pure gold, however it’s considered too soft for use in jewellery, and is alloyed with other metals to strengthen it.

Kimberly Process:  Also referred to as KPCS- Kimberley Process Certification Scheme. The Kimberley Process (KP) is a joint government, industry and civil society initiative to stem the flow of conflict diamonds (rough diamonds used by rebel movements to finance wars against legitimate governments). The trade in these illicit stones has fuelled decades of devastating conflicts in countries such as Angola, Cote d'Ivoire, the Democratic Republic of the Congo and Sierra Leone.

Lustre: Lustre is the amount of light that is reflected back to the observer from the surface of the jewel.

Loupe:
  A small magnifying glass (usually 10x) used to view gemstones.

Marquise:
  An oval shaped gemstone cut with pointed ends. It's named afer the Marquise de Pompadour, mistress of King Louis XV.

Master Stones:
  Diamonds of known colour grades used to grade other diamonds.

Melee:
  Small diamonds usually less than about 10 points.

Mill Grain Edge:  A look, which is knurled, or has the look of small beads or ridges on the edge of the jewellery piece.

Near Colourless:  A general term for diamonds in the G-to-J colour range, and the bulk of the diamond market. This is also where Moissanite’s colour falls.

Padparadscha Sapphire:  A rare pink-orange variety of corundum. These gems are mined in Sri Lanka and usually heat treated to improve and intensify colour.

Pave: (Pah Vay) A style of setting small stones very tightly together, as in a pavement or paved with diamonds.

Pavillion:  The lower portion of the jewel, below the girdle. It is the cone shape of the diamond.
Pavilion Angle: The angle measured between the girdle plane and the pavilion main facet.

Pear Cut: A fancy shape diamond that resembles a teardrop or pear. The Pear Shape is a combination of the Oval Shape and the Marquise Cut.

Platinum:  A rare precious metal used in jewellery. Platinum is naturally white and is favoured for many ring settings because of its durability.

Plotting Diagram:  A diagram in a Diamond Grading Report, which shows approximate location and type of internal and external characteristics.

Point:  A trade term used to describe the weight of diamonds. One point is equivalent to one-hundredth of a carat. For example, a 1/4 carat diamond, equals 0.25ct, equals 25 points.

Polish: The smoothness of the surface of a diamond which shows no visible wheel or burn marks. Polish is regarded as one of the indicators of the quality of as diamond's cut; it is graded as Ideal, Excellent, Very Good, Good, Fair, or Poor.
 
Polished Girdle:  A girdle of a gemstone that has been polished to give it a smooth surface.

Post:  A pin-like finding attached to an earring. It passes through the pierced earlobe and may be held in place by a backing.

Poor Cut:
An inferior cut diamond that can be either cut too deep or too shallow which will lose or leak light through the side or bottom resulting in less brilliance and value.

Princess Cut: A square or rectangular-shaped modified brilliant cut diamond.

Prongs:  Several tips or clamps used to hold the jewel in place; also known as ‘claws’.

Radiant Cut:
A type of brilliant cut fancy shape that resembles a square or rectangle with the corners cut off.

Reflection: The bouncing back of light when it strikes an external or internal facet on a polished diamond.

Refraction: The change in direction of a ray of light as it passes obliquely from a medium of one optical density to a medium of a different optical density, as from air into water or from air into a gemstone. This means that the light bends as it enters a diamond because the light travels through air and the diamond at different speeds.

Refractive Index:  The ratio of the speed of light in air to its speed in a gemstone; the degree to which light is bent when it passes through a gemstone. The RI of diamond is 2.42 and the RI of Moissanite is 2.65.

Rough:  An uncut and unpolished jewel or gemstone in its raw state.
Rhodium Plating:  Rhodium is a metal that is part of the platinum family. White gold is commonly rhodium plated in order to give it a very white lustrous finish, because white gold is not purely white but instead has a yellowish tint. Rhodium is also used on silver to prevent it from oxidizing. Rhodium plating should be done on white gold and silver jewellery once a year to maintain their lustrous finish.

Round Brilliant Cut: This is the most common cut for a diamond. The standard round brilliant "full cut" diamond consists of a total of 58 facets: 1 table, 8 bezel facets, 8 star facets and 16 upper-girdle facets on the crown, 8 pavilion facets, 16 lower-girdle facets, and usually 1 culet on the pavilion.

Scintillation:
  When light reflects from a diamond, the sparkling flashes that come from the facets of the gem are known as scintillation.

Shallow Cut: When a diamond is cut too shallow, it will lose or leak light through the side or bottom. This results in less brilliance and value.

Shank:  The part of the ring that encircles the finger and to which the setting is mounted.

SI1 & SI2:  GIA Clarity Grade for Slightly included, noticeable inclusions that are easy (SI1) or very easy (SI2) to see.

Single Cut:  A cutting style with a table, 8 crown facets, 8 pavilion facets and sometimes a culet. Single cuts are more common for small diamonds weighing less than 10 points.

Solitaire:  An individual jewel set by itself in a piece of jewellery.

Sparkle: The liveliness of the light reflecting from a diamond; the sum of the brilliance and the fire

Step Cut:  Rows of facets that resemble the steps of a staircase. The Emerald and Baguette cuts are examples of the step cut.

Sterling Silver:  Silver that is at least 92.5 percent pure with 7.5 parts of another metal.

Symmetry: A grading term for the exactness of shape and placement of facets. Grading reports will often state the diamond’s symmetry in terms: Excellent, Very Good, Good, Fair, or Poor.

Table:
is the largest facet on the top of a cut diamond. It has an octagonal shape on a round brilliant.

Table Percentage: For a round brilliant, it is determined by dividing the largest table diameter by the average girdle diameter, expressed in percentage. So, a diamond with a 60% table has a table, which is 60% as wide as the diamond's diameter.

Table Spread:  term used to describe the width of the table facet, often expressed as a percentage of the total width of the stone.

Total Depth Percentage: The depth from the table to the culet, expressed as a percentage of the average girdle diameter in a round brilliant.

Tension Setting:
  A diamond is held in place by the pressure of the band’s metal, which is designed to squeeze the stone.

Trillion Cut:  A type of brilliant fancy shape that is triangular with rounded sides.

VS1, VS2: GIA Clarity Grade for VS means Very Slightly Included. VS grade diamonds have minor inclusions ranging from difficult to somewhat easy to see.

VVS1, VVS2: GIA Clarity Grade for VVS means Very Very Slightly Included, contain minute inclusions that are difficult for even a skilled grader to locate under 10X magnification.

Well Cut:  Well cut proportions ensure the maximum compromise between fire and brilliance. When light enters a properly cut diamond, it is reflected from facet to facet, and then back up through the top, exhibiting maximum brilliance, fire and sparkle.